Steam superheater



Apri& 99 1929. H. CRUSE '11,7U8,54-

STEAM SUPERHEATER Fil d May 12, 1925 5 Sheets-Sheet 1 i (9 E `N F 6 & v ////////////////Y////////////////////// W %I (C W//////////// //////////////////////////,V//

6 1 i& M e/%f Hen/y Gra/.Se.

a `7/////L///// ////////////////////M Aprfl 9,192& H. cRUsE STEAM SUPERHEATER 5 Sheets-Sheet Filed May 2, 1925 Apr'fl 9, &929, H. CRUSE STEAM SUPERHEATER Filed May l2, l925 3 Sheets-Sheet W///// //////fl #emm &use %rr m; O a

Patented Agon 9, 1929..

shiten states hasani? HENEY CRUSE, OF HYDE, ENGLAND.

STEAEI SUPEBHEATER.

Application filed May 12, 1925,' Serial No. 29,742, and in Great Britain May 19, 1924.

This invention relates to improvem'ents in steam superheatei's and whilst it has particular reference to superheater elements for use in the smoke tubes of locomotives and marine and the like boilers may nevertheless he used for superheating steam in other services where its application would be useful and effective, the object being to provide a superheater element or elements which will give increased etlicency whilst at the same time being simple in Construction.

A further oh'ect is to provide improved means for coupling up the superheater elements either directly to each other and/or to the 'headers or distrihutor and collector :tor wet and superheated steain.

My invention has for its object to provide an improved form of superheater element or tube primarily ?tor use in the smoke tubes of locomotive, marine and the like, boilers.

I In its simplest form the superheater element according to the invention consists of two tuhes formed into two semi-circular or substantially semi-circular tubes closed at i their longitudinal tacing edges and ends and each embodyiny a comparatively 'thin semiannnlar steam race or space between its inner and outer walls; a central through passage for heating gases formedby joining the tubes together atthe longitudinal edges and ends; passages for connecting the two steam races i oi' spaces and for returningthe steam to the enter ends and coupling means'tor conducting the steam from one element to the element next adjacent to it or toa couplingelement or header common to a series of tube elements which header elements in turn are connected to the wet and superheated steam headers 'or distrihutor and collector. V

My invention will be ully described with reference to the accompanyng drawings in which,

Fig. 1, is a lonn'itudinal sectional elevation of one of the tube elements,

Fig. 2, elcvation oi 'same showing the welding; of the semi-circular tnhesat local points,

Fig. 3, cross section on line 3-3 of Fie 1,

` Fig. 4, cross section on line 4% of Fig. 1,

Fig. 5, fragmentary longitudinal section to an enlarged scale showing one form of'construction of the inner end of the tube',

Fig. 6, longitudinal section' to an enlarged scale showing a series of tube elements a rranged in thesmoke tubes of a locomotive or mafi neoi like boiler and means jfor connect ers 01' the like,

ing-their oute'r ends together and to the head- Fig. 7, end elevation, partly in section, on l ne 7-7 of Fig. 6, showing` the tube connectiondevice or header and Fgs. 8 9 and 10 sectional side elevations and section respectively showing different means for coupling two tube elements together.

Fig. ll is a fragmenta'ry view on an enlarged scale showing another form of construction of the inner end of the tube.

Inca'rrying out'my invention and referring particularly to F l to 4 each superheater element consists of two semi-circular tuhes a and a each a half tube containing a comparatively thin semi-annular race or stean space?) betweenits inner wall c and outer wall (Z. In the truly semi-circular form this space would have concentric sectional walls as shown in Figs. 3 and 4:, though on the other handl may depart from such true form hy pressing one 01 the walls nearer' to the other at its central cross sectional point, or both walls may he somewhat distorted. he longitudinal edges e of the semi-circular tnhes 'are closed and may he fiat as shown or of' semi-circular formation and in either case he welded together at local points f or through- .out the full length ot' the oining sui-faces i though, on the other hand, I may'securc theni together with other convenient means such,

' clips or the like. The tuhes so connected are placed in position within the fire oi" 811103* tubes g Figs( &and 7, so as to be concentric therewithleavingan annular space or passage &between the outer wall of the superheater tube and theinner wall of the smoke tube for the passageof a portion of the heating gases from the firehox; and acylindrieal or suhstantially cylindrical central passage 2' formed inside 'the inner walls c'i-the superieater tube for the passage oi? the renainde: of the heatinggases to the smoke boxa.

At the inner end O' that end ot the element insidc'the fire or smoke tube the two semi-cir- 'onlar tuhes formingthe element-may be connected together ll) bya short annular tube 12 closed at one end and open at the other 'to embrace the walls ofthe two semi-circular tuhes and be suitably screwed and/or welded thereto, or the annular' connection tube may consist of two short tubes of different diameterclosed by welding 'or other means at their outer ends. 'Other devices he used but in all cases designed to form an annular connection 'for the semi-circular tubes which allows for the passage of steam from the race or steam space o one hal' tube to that of the other in opposite directions.

In another form I may return the steam stream from the space b in one semi-circular tube to the other at the inner end byrmeans of an annular chamber by cutting away the edges or webs e for a short distance from the extreme end as at f','and closingthe space by a ring m fitting the space and preferably welded in. 4

I may attach a gas shield n to the ring by screws n or WGlClSHCll shield to the rin Or the ring and shield may be integral and be welded to the tubes. I' may. form the outer end of the shield n with a somewhat sharp end asshown to more efficiently divide the heating gases into streams, one to pass through the annular space ?L between the superheater tube element a and the smoke tube g and the other stream to pass through the centre space i of the superheater tube element.

'In the preferred. form for connecting a se -ies of tubesa with each other I employ a chamber or header as shown in Figs. 6 and 'Z common to them all into which the outer walls CZ ot the outer -ends of the tubes a may be shrunk or otherwise tightly 'fittech such out-er walls being cut away at 19' to form passagcs for the steam n the process of superheatin t hen not shrunk into the chamber o each tube element may be connected to such chamber by providing it witl a fixed collar q having a tubular ball ended neck 7 fitting in a correspondingly shaped groove in the inner wall of the chamber and a tubular nut s having a ball ended neck of the character re-` ferred to such nut being tightened up on' the sc1'ew'-tl1readed` end'ofthe tube. lhe annular space at such end is closed in by a ring t welded into thetube. 'The arrangement permits each tubevto be semrately and jreadily removed* fron its position inthe chamber or header 0. The la'tter is coupled at one end to v 'the wet'steani header or distributor u and at the other en d` to the superheated steam header or collector e by any suitable device asfor instanceby soekets w, the outer ends of which are provided with capnuts y In the a roresaid arrangement the steam to be superheated passes from the wet steam header first into the chamber 0, then along the semi-annularspace of one -halftube to the 'inner end andthence through the seni-annu lar space of the other half tube into the chame .ber 0 and SO onthroughout the whole oti-he tubesof; the series to the superheated steam header. i The heated gases of the combustion i 'pass through the annular space h between the smoke tube g and superheater element w, a

and through the central space in 'the l'atter.

From the foregoing arrangement itwill be seen that when the element s fitted into the flue tube two clear gas runs are formed permittin: of free travel of the heating gases 'from firebox to smoke box.

In the annulus h the dual function of the gases is to heat the boiler water through the fine tube a' and to superheat the steam in the races b of the element; the major portion of the heat transmitted going through the flue tube to the boiler water. In the central core or 'area z' the sole function of the gasesis to superheat the steam travelling through the surrounding races from end to end, to and fre of the element i comes a fire-tube afiected solely to the efiicient superheating of the steam travelling at high velocity around it. The element a, ai

is held in the flue tube luge l suitably placed y In Eigs. 8, 9 and 10 I have indicated'by geby short strips or way of example other means to those de-v scribed in connection with Figs. 6 and' 7 i'or coupling` up the superheater elements. V Thus in Fig &each element a, a has short radiating tnbes 2 internally screw-threaded coup'lcd by short tubes 3 externally screwthreaded. In F 9,` the short tubes 2 are coupled by fianged tubes 4, the fianges of which are bolted together. In Fi 10 the short tubes 2 are externally screw-threaded and each is fitted witha tubular sleeve' in screw-'threaded union 9 h aving an internallyprojecting fiange 10 hearing on a shoulder ll of the upper sleeve 5 The union 9 is screwed up to form a tight joint betweenthe sleeves 5.'

I do not conine myself to the' detail Varrangement her inbefore described forcon:

necting the 'superheater elements to j each n other as these 'may be vared without departing "from the essential characteristies ofmy nvention. p i

I would have it ,understood that I 'may arrange two ormore superheater tube elements within a single smokeor othertibe instead of employing' one element only.` e i What I claim as iny ii'ventien 'and desireto secure" by Letters Patent is z- Thisgas core thus bea l A superheater element comprising `two substantia'lly seni-'annular tubes connected at their longitudinal edgesto .form tubular passagei or the flow of hot-gasespopenings provided on the outer 'walls of each near' one end `for admission steam to enet-and ,discharge ot steam rom 'the Other, :means closing each -semi-annular tubeat this end, and means at the other end of said tubes 'forming -an annular passage conneeting the` two tubes to enable steam fiowing uponetubeto flow down the other tube in contrary direction.

2. A pluralty ef alned superheatei elements each constructed from two substantially seini-annular tubes connected at their longitudinal edges to form a tubular passage ter the flow of hot gases, openings provided on the outer walls of each tube near one end tor admission ot steam to one and discharge et steam from the other, means closing each semi-annular tube at this end, means at the other end of said tubes forming an annular passage conneeting the two tubes to enable steam flowing up one tube to flow down the other tube in contrary direction, in combination with a pair of headers and means to connect the suo erheater elements seriatim to each other and the first and last of them to the two headers respectively.

3. A plurality ot superheater elements each constructed according to claim l in combination with a row of ahned flues into which the elements extend; a tubular member located directly in front of said row of fiues through which said elements extend transversely, the openings on the outer walls ojf the semi-annular tubes communicating with the interier of the tubular member, the arrangement being such that each element interrupts communication of the part of the interor o' the tubular member on one side of the superheater element with that on the other except by way=of the two semi-annular tubes and the annular eonnecting passage at their further ends.

4. The combination of an element according to claim 1 with an elongated hollow body whose interier width is slightly less than the eXterior diameter of the element, the hollow` body having an aperture through it through which the element extends, the openings on the outer walls ot the semi-annular tubes opening into the hollow member in opposite directions, a collar fixed to said element and hearing againstsaid hollow body to make a tight joint, and a nut screwed on the element, said nut hearing against the body and making a tight joint.

5. A superheater element comprising two substantially seni-annular tubes connected at their longitudinal edges to form a tubular passage for the flow of hot gases, two openmgs on opposite sides in the outer walls near one end tor the admission and dischargc semi-circular trough, said troughs forming a central eircular fine when the tubes are ioined together, each oi? said tubes having means adjacent one end 'or the admission of steam to one and the discharge of steam from the other tube, means cl-osing each tube at this end, and an annular member at the other end connected. to both of said tubes to close the same, the said tubes and member being censtructed and arranged to establish a communication between the tubes at this other end so that steam can flow from the admission means in one direction through one tube and back to the discharge means through the other tube.

In testimony whereo'f I have hereunto set my hand.

I-IENRY CRUSE. 

